ISO 15189, Medical laboratories--Particular requirements for quality and competence was prepared by ISO/TC212, Clinical laboratory testing and in vitro diagnostic test systems, and its first edition published in 2003 and the second edition in 2007. Its purpose is to be used by medical laboratories in developing their quality management systems and assessing their own competence, also for use by accreditation bodies in confirming or recognizing the competence of medical laboratories. Since its publication, it has been recognized officially by the International Laboratory Accreditation Cooperation (ILAC) to be used as the international standard for the accreditation of medical laboratories worldwide. In Japan, the Japanese Committee for Clinical Laboratory Standards (JCCLS) and the Japan Accreditation Board for Conformity Assessment (JAB) cojointly started the accreditation program in August, 2005, and a total of 46 medical laboratories had been accredited by April 2009. In ISO/TC212/WG1 is working on the preparation of its third edition.